Dynamic sea clutter simulation at low grazing angles

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2018
Erdoğan, Muhammed Z
High-amplitude clutter signals may be observed during radar operation due to environmental objects having large surface areas. By Doppler processing, modern radars can discriminate between echoes from mobile targets and echoes from stationary objects like mountains, buildings and so on. However, there is no simple way to do this discrimination for sea clutter since sea is always on the move. Therefore, statistical and empirical models are frequently used to characterize sea clutter. Yet, such models are unlikely to predict sea clutter accurately, particularly in complex sea conditions. In this thesis, we approach this issue in a different way. Dynamic simulation of sea clutter is performed to obtain more accurate results. In this simulation, sea surface is modeled depending on time-varying environmental factors, like sea wave height. Therefore, change of clutter is compatible with temporal and spatial correlation of sea surface. Then, a model is suggested to mimic realistic sea clutter parameters like normalized radar cross sections and Doppler frequency shifts. By applying the suggested model to the generated sea surface in certain time periods, complex radar data matrix is constructed. Finally, the simulation results are analyzed and compared to some of the available experimental data for different scenarios, and good agreement is observed.

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Citation Formats
M. Z. Erdoğan, “Dynamic sea clutter simulation at low grazing angles,” M.S. - Master of Science, Middle East Technical University, 2018.